Conventionally, a two-agent hair dye composed of a first agent comprising an oxidation dye and a second agent comprising an oxidant such as hydrogen peroxide has been well known. The first agent and the second agent of the two-agent hair dye are filled in different containers, and a high hair dyeing effect can be achieved by mixing the agents just before use and oxidizing the oxidation dye.
The two-agent hair dye is proposed to be a two-agent aerosol product that can discharge the first and second agents simultaneously to facilitate preparation of mixing the first and second agents (Patent document 1). The discharge forms of the two-agent aerosol product are foam, cream, or the like and foam type is preferably used especially because the preparation of mixing is simplified, it can be spread on hair easily, it is difficult to drip, and thus it is easy to be handled and can be used readily. Most of the foam-type two-agent aerosol products are upright style where the container is used upright, and its aerosol valve comprises a tube that opens at the bottom of the container.
The foam-type two-agent aerosol product can be, for example, as shown in FIG. 5, manufactured by filling a first agent concentrate and a second agent concentrate in container bodies of a first agent aerosol container 101 and a second agent aerosol container 102, respectively and fixing respective aerosol valves comprising a tube, sealing the containers, filling a liquefied gas from the respective aerosol valves, coupling the first agent aerosol container 101 to the second agent aerosol container 102, and mounting a discharge member 103. With reference to FIG. 5, A is referred to as the first agent concentrate and the second agent concentrate, and B is referred to as the liquefied gas.
However, when the foam-type two-agent aerosol product is stored for a long period of time, or stored for a short period of time in a high-temperature environment, a discharge performance may be degraded and further discharge may be impossible in the first agent aerosol container. Therefore, an aerosol product that can endure storage for a long period of time or in a high temperature environment is required.